GEOLOGY --- HAMILTON GROUP --- THE LOWEST ROCKS IN THE COUNTY --- TULLY LIMESTONE --- GENESEE SLATE --- PORTAGE OR NUNDA GROUP --- ITHACA GROUP --- CHEMUNG GROUP --- CATSKILL GROUP --- DECEPTIVE INDICATIONS OF COAL --- QUARTERNARY DEPOSITS --- CLAYS --- SULPHUR SPRINGS.
Chenango County is covered by the old red sandstones of the modern classification, or the Erie and Helderberg divisions of a former period, the Catskill group of the latter division being probably the only one of its members in the county. The lowest rocks in the county are the Hamilton group, which appear upon the north border. Successively above these toward the south appear the Tully limestone, Genesee slate, and the Portage, Ithaca, Chemung and Catskill groups.
The Hamilton group is confined to the towns of Sherburne, Smyrna, Columbus and New Berlin, a strip only extending into the latter two towns along the Unadilla, and passing under the higher rocks below the village of New Berlin. It is well exposed along Handsome Brook to the north-east of Sherburne village, exhibiting a mass from sixty to one hundred feet thick, chiefly of the dark-colored shale of the group, and abounding in its characteristic fossils. The shale constitutes the fall of the creek, and extending towards its mouth, is soon lost under the covering of alluvion and soil. This is the most southerly exposition of the group in the Chenango Valley. The same mass appears east of the village of Smyrna, beyond which, at a lower level, are those of the upper rocks, exposed at Madison University, at Ladd's quarry, and on the canal above Sherburne. The ridge from Madison county, composed of the Hamilton group, appears to incline rapidly near Sherburne, so as to expose the Sherburne flags about two miles below that village. The group is exposed in the sides of the creek in the north part of New Berlin, and at the quarry and milldam back of New Berlin village, on the road to the Chenango valley. The fossils are numerous and the same in all respects with those in the creek near Sherburne.
The group, though but little exposed in the county, presents four points of interest; the first in Ladd's quarry on the canal, near the line of Madison county, in the continuation of the range of West Hamilton. The quarry is rich in many of the fossils of the group, being in all respects like that back of Madison University, near the top of the hill. Considerable stone was taken out, being convenient for transportation. The second point is the falls and bank of Handsome Brook, north of Sherburne. The water falls sixty or more feet expose about a hundred feet of the finer kind of shale. Many fossils, which are common in the mass below the encrinal limestone at Ludlowville, and the mass of the group generally, may be obtained at the creek.1 The third locality is on the road from Hamilton to Smyrna, where the two kinds of rocks are seen, as well as the common fossils of Hamilton and the shale of Handsome Brook, the latter above the former. The fourth point of exposition is at the creek and quarry west of New Berlin village, which does not differ from those near Sherburne, but the rock is coarser and harder.
The fossils of the group, the Macronated delthyris the Flabella avicula, Keeledatrypa, Syrtalis stroph-omena, Plebian atrypa, Prow delthyris, De Kay's dipleura, Goniatites punctatus, etc., are found in great abundance, especially at Ladd's quarry, which is a little above the canal. In most cases the calcareous particles of the testaceous fossils have been removed, and their place in part occupied by hydrate of iron, forming a pleasing contrast with the yellow-gray color which the rock assumes after exposure. In Ladd's quarry, the State Geologist, Lardner Vanuxem, found on a thin slab two or three small perfect trilobites, with the same caudal structure which distinguishes the English genus, and associated with the Dipleura of the same size, the largest not over an inch in length. The only difference observed between them was the tail. "This fact," says Vanuxem, "settles the question of difference as to genus, which, with the British geologists, appeared to be doubtful." The specimens are in the State collection. With the exception of two instances only in an upper position, this trilobite is confined to the Hamilton group. It is rare in the fine slate or shale, but common in the coarse shale and sandstone.
The Tully limestone takes its name from the village of Tully, near which it is quarried and burned for lime. It is of importance, being the most southern mass of limestone in the State, and as a dividing line easy to find in all the counties where it exists, separating two important divisions of rocks. It is an impure limestone, fine grained, usually of a dark or blackish-blue color, often brownish. The mass is more or less accretionary, breaking into irregular fragments which are usually small, owing to the particles of carbonate of lime separating from a mixed mass at innumerable points. The Usual thickness is about fourteen feet; the greatest observed thickness, twenty feet. It makes a good, but not a white, lime; owing, in all probability, to the presence of carbonates of iron and manganese. Minute veins of carbonate of iron are seen in the limestone; and the fossils of the rocks above it are often replaced by the two carbonates, particularly the encrinital stems and disks.
It has not been seen east of the town of Smyrna; but west from thence it extends through the Counties of Madison, Onondaga and Cayuga, and further west, though it has no exposition in Madison County. The first and only point in the county where it is observed is on the turnpike from Sherburne to DeRuyter, about eight miles from the former village, in the north-west part of Smyrna. It appears in a low side-hill, forming the bank of the creek where the road crosses it. About four layers are exposed, ranging by the side of the creek. It is more impure than further west. It next appears in Onondaga county, about two miles north-west of DeRuyter village. It terminates all those deposits in which calcareous matter forms an essential part. There are two fossils wholly peculiar to it, the Cuboidalotrypa and the Tully orthis.
The Genesee slate, though it appears at New Berlin, was not distinctly recognized east of the town of Smyrna, owing probably to its intermixture with sandstone. West of that town it may be seen at several points along the road from Smyrna to DeRuyter. It underlies the latter village, and appears in all the side-hills around it. But it does not form the same well-defined rock to the east that it does to the west.
It is an argillaceous fissile mass, which, with great propriety, may be termed, according to English local geological phraseology, a mud rock. Its color is black and very uniform; its structure also preserves the latter quality. It is more or less slaty and somewhat hard and brittle; but, like all the upper fine-grained argillaceous rocks of the district, though its edges resist the weather, its surface, when exposed, falls into pieces and readily decays. The joints in the rocks are two in number, usually well defined, and their direction nearly at right angles to each other.
This rock contains but few fossils, which are not generally diffused, but are quite numerous in a few localities on Cayuga Lake. Few or no fossils have been observed, except fucoids.
The Portage and Ithaca groups appear to be the surface rocks of the town of Lincklaen; of the west part of Pitcher and German; of Otselic; the north part of Pharsalia; all those parts of Sherburne, Smyrna and Columbus not occupied by the lower rocks; all but the south-west part of Plymouth; the north and west portions of North Norwich; extending on both sides of the Chenango below the village of Oxford; and the east side of the town of New Berlin, with the exception of those parts towards the river, where the rocks of the Hamilton group hold position.
Numerous quarries of building and flagging stone are opened in all the different towns of the groups, in the lower part of which the better kind of flagging stone occurs. At Skinner's quarry, south of Sherburne, the flags examined were large and smooth; but the quantity of shale and slate upon them was considerable. At Church's quarry, about two miles south of that village, they were more accessible, but not so good. The opening here was about twenty feet in depth upon a side-hill, rising about forty feet above the valley, and showed dark-blue or blackish slaty shale with the sandstone. The same appears in the quarry back of New Berlin village, and shows the graphic fucoids of Cayuga Lake, Ithaca, and other localities. At Harris' quarry, west of North Norwich, which was opened for the Chenango Canal, the stone exhibits a fair sample of the quality of the group generally. Fossils are somewhat numerous, and it is the second best locality of the Curtain fucoid. At Norwich many quarries have been opened in the hill to the west of the village and elsewhere; the stone is inferior in quality to that of the upper group. Among the rocks around Norwich appear three fossils common to the Hamilton group, the Posidonia lirata, Strophomena carinata and Atrypa plebia, showing that localities existed which favored the continuance of certain species long after their total destruction in others. Two other fossils are very generally distributed throughout this group, which are considered to be the same as the Linear and Umbonated Strophomenę of the Hamilton group.
The Portage or Nunda group may be considered the commencement of the upper part of the Erie division, considering the Tully limestone and Genesee slate as dividing masses; the Tully limestone, however, properly forms the terminal portions of the lower part of the division, and the slate of the intervening one. At Sherburne this group presents more of the hard sandstone layers than in the west, where the hard coarse shale predominates.
The rocks of the Ithaca group consist of a series of coarse hard shales and sandstone, the whole generally of a dark color, and without any observed definite arrangement. A few of the sandstone layers are regular in outline and resemble some of those which belong to the group below; but this is rare.
In this group those highly curious fossils, the Caudagalli fucoids, are well defined, and more extraordinary in shape than in their lower positions. At Burdick's quarry to the south-east of DeRuyter village, on the hill, near the foot of which the Genesee slate is seen, covering the valley, and along the road towards Smyrna, these fucoids are quite numerous and cover a considerable extent of surface. The greater number are the kind compared to the folds of a curtain by Dr. Locke, of Ohio, who also found them in the Waverly sandstone of that State. A second locality is the Harris quarry, near the top of the hill to the west of North Norwich. In the State collection are a number of these fucoids, obtained from DeRuyter and this quarry, "which," say Vanuxem, "will not fail to convince the most skeptical that the nature or origin of these singular productions was organic and vegetable."2
The Chemung group is rather obscure in the county except in the town of Greene. But little was positively recognized in the Chenango valley to the north of that town; "although," says Vanuxem, "from its great thickness south and west it should there appear; but it is also possible that it terminates short of the north line of the Catskill group, which may extend beyond it as at Oneonta, where no part of it was recognized, and where the Catskill group appears to repose immediately upon the Portage and Ithaca groups, or a mass which corresponds with the sidehill quarries at Norwich and Port Crane, and which, by the fossil character, are referable only to those groups."
The group consists of sandstones and shales, more or less slaty, and mixtures of the two in endless proportions. The former furnishes good building and flagging stones; the latter is often of soft, decomposable masses, but in less degree than the shale of the Hamilton group. The sandstone in the north part of the group shows well defined layers, in which respect it resembles the lower ones. The sandstone is of a lighter color than the lower group, the greenish or olive color being more general, and the shale more disposed to assume the same color when altered-concretion of a large size often appear in the shale and sandstone, the nucleus being more solid than the surrounding parts. Carbonate of iron often replaces its fossils, particularly its encrinites, which are usually about half an inch in diameter and different from those of the Ithaca or any rock below it. Some of the sandstone masses are loaded with shells, the cement being limestone, making a more durable building stone; and some of the varieties make good fire stones from the mixture of shells.
At Cameron's quarry in Greene was found the large species of Tricircled encrinite, a very characteristic fossil of this group. Is consists of three different sized crinoid joints, grouped together. It is usually replaced by lamellar carbonate of iron colored yellow or buff.
The Catskill group is the immediate predecessor and the base, therefore, of the coal formation. It is the terminal group of the New York series, and therefore holds the highest position relatively to the other rocks, capping some of the elevations in this, Broome, Otsego and Tioga counties, to which it is entirely confined. It has an extensive range in the county, covering a large area of the high ground between the Unadilla and the Chenango and the Chenango and Genegantslet, extending in places to the west of the latter stream. It coves the towns of Bainbridge, Coventry, Guilford and the greater part of Oxford; receding a few miles below Oxford village from the Chenango, also from the Unadilla to the north of Guilford, diminishing in width between the two rivers, and terminating in the towns of Sherburne and Columbus. West of the Chenango it appears about a mile or so to the north of the village of Greene, forming part of the mass in the town of Oxford; and extends north on both sides of the Genegantslet, covering three-fourths of the town of McDonough, the greater part of Preston, the south-west portion of Plymouth, and the larger south half of Pharsalia, its northern limit being in the latter town.
The group affords better building materials than the lower rocks of the southern counties, especially the grindstone variety, which occurs to the west of Chenango River. This latter rock is abundant in the towns of Preston, McDonough and Pharsalia. It is easily wrought, of a good lively color, hardens by exposure, and is the handsomest building material of the whole of the southern counties. The court-house at Norwich is built of this material.
It consists of light-colored, greenish-gray sandstone, usually hard; of fine-grained red sandstone, red shale or slate; of dark colored slate or shale; of grindstone grit; and of a peculiar accretionary and fragmentary mass, appearing like fragments of hard slate, cemented by limestone. This mass, though usually but a few feet in thickness, is a constant associate of the group, and is well know in England as cornstone.
The structure which the hard gray sandstone often presents, is also highly characteristic of it. It appears in many localities, generally forming the surface rock, usually in layers of from four to ten feet thick, and nearly horizontal in position. Each of these layers is subdivided into numerous parts, one or more inches thick, often disposed in oblique divisions; the surface of some is straight, others bent; the divisions usually overlap each other, and show considerable symmetry, presenting altogether a singular conformation, and a highly picturesque rock. Where this rock has not been exposed for a long time to the weather, the structure is not so obvious as in those masses which for ages have been subjected to it; the latter exhibiting it fully. Among the many localities where this structure exists in the most marked manner, is one on the road from Norwich to New Berlin, near Matthewson's Pond; on the west side of the Chenango, above the village of Greene, and on the Genegantslet, above the same village.
The oblique lines of structure are highly characteristic of the gray sandstone of the Catskill group as it appears in Chenango county. "Three causes," says Vanuxem, "present themselves in explanation of this structure: first, oblique depositions by water or wind; second, infiltration of water, carrying and depositing the finer particles in an oblique manner; and third, the crystallization of one or more of the constituents or parts of a rock in which this structure exists."
Between the Catskill and Chemung groups no line of demarcation was observed. In ascending from the Chemung group, the first signs of change which usually appeared was a diminution, then a disappearance, of the fossils of the Chemung, a more solid or hard rock succeeding, often accompanied by red sandstone or red shale, and the gray sandstone sometimes accompanied by thin beds of cornstone, which readily attracts the eye, when long exposed to the weather, from its cellular appearance and dark umber color; the former caused by the removal of accretions, etc., of limestone, and the latter by the oxidation of iron and manganese associated with the calcareous material. Above all these, and usually capping the whole, was the complex-structured sandstone.
The group is very barren in fossils; the only ones observed in this State which could with certainty be referred to it being the Catskill cypricardite, (C. Catskillensis,) the Narrow cypricardite, (C. angustata,) and the half probably of a third species, from Richmond's quarry above Mt. Upton; but no other fossils, except vegetable remains of the smoother sort, or rather the kind without marks or configurations, having simple lanceolate forms.
In this group, both in England and Pennsylvania, are the remains of a peculiar class of fish, which show the value of the fossil character, since the position of the rock is well established; holding the place of base to those of the coal in both countries; being above the Devonian system according to some geologist, or forming its other member according to others, just as it may be included in or excluded from that system. These remains have been found in many places in Pennsylvania. As yet but small fragments only have been found in this State. They exist in the cornstone near Oneonta, and in the same mass near Oxford, and, no doubt, will generally be found in that fragmentary portion. The small fragments in the cornstone show that besides containing accretions of limestone or carbonate of lime, it also contains those which have been subjected to a mechanical action, which has rounded some of its particles.
Though shells and bones are rare in this group, plants appear to be much more numerous; accumulations existing similar to those of the Ithaca and Chemung groups, but in greater number and frequency, and giving rise to their seams of coal, none of which, however, exceeded a foot in length and breadth, and an inch in thickness; and they were generally found in the gray sandstone rock. These accumulations are rarely accompanied by pyrites, the decomposition of which stains the rock of an ochery color. The sandstone, coal and ochery appearance being three of the common characters of coal in its proper series, is the reason why the strongest hopes have been entertained of finding coal where they exist, the great fact of position and more important associates of the coal beds being overlooked.
The rock of this group is quarried on the west side of the Chenango, north of the village of Greene, where it is but a few feet above the road, and shows thick beds subdivided into courses obliquely arranged. It is hard and unchangeable. On the east side is the McNeil quarry, four miles south of Oxford village. It produces flags, step-stones, etc., some of which are sent to Binghamton.
Quarternary Deposits, though not as abundant in this county as in some localities, exist here. These are of two kinds, first, those which have been transported from a greater or less distance, as clay, sand, gravel, boulders, etc., and are commonly known as alluvial deposits, or products of alluvion; and second, the deposits in place from solution, as lake marl, calcareous tufa, ferruginous tufa, or of the products of vegetation, as peat or muck.
There are numerous points where the alluvion appears to have been formed over the hill side; such is the mass west of Onondaga village; the decent into the valley north-west of Waterville; and north of the village of Greene, in the Chenango valley. These deposits of alluvion, near the line of dividing waters, greatly resemble certain accumulations of similar deposits noticed in the survey of Massachusetts, called diluvial elevations.
Immense accumulations of these alluvial deposits exist south of the north line of the Helderberg division, either filling up the valleys and forming level surfaces, or ranging by the side of the valleys as terraces, or thrown into irregular hills in the valleys, and also occurring on the heights apparently in no regular order. They consist of rolled stones, large and small, sand, clay and earth. The rolled stones are in prodigious quantity; nearly two-thirds of them form rocks north of the Helderberg range. They consist chiefly of primary rock and gray and red sandstone. In some localities those of limestone are numerous; and when they exist, as their graveland soil are often present, they give rise to deposits of tufa or lake marl; the former kind if air only be present, the latter if deposited in water.
The excavation of the Chenango Canal from Oriskany Falls south is entirely in alluvial materials; showing frequently in the northern part of the town of Madison a mass of gravel and large rolled stones as an upper deposit. Below the rolled stones there is often a deposit of blackish or dark-colored sand, fine or coarse, which is the common sand of the whole of the south valleys. The lighter colored sands exist, but are rare, comparatively. The lower part of the canal at Chenango Forks was in the sand of this kind, above which was a mass or coarse gravel from six to eight feet thick, with rolled stones from one to eight inches in diameter, having on the top finer gravel with thin layers of sand.
The clays in this locality are usually of a lighter color than those of the Mohawk; the dark ones exist, but are rare. Small pebbles of limestone appear to exist also in the clay, as at Norwich. Some of the bricks are thus apt to burst and crumble after being burnt and exposed to the weather. This shows the northern origin of at least a portion of the materials.
There are several sulphur springs in the county, the water from many of which has been used with benefit for cutaneous diseases. Among these is one which issues from the slate of the Hamilton group, at the foot of the falls on Handsome Brook, near Sherburne village; Shee's Spa, in the south edge of McDonough; one, two miles from Norwich village, "which has been much used for cutaneous disorders"; one in the town of Pharsalia; several in the east part of Pitcher, which made that town at one time a place of popular resort; all of which emit sulphuretted hydrogen."3